Slider for a slide fastener

ABSTRACT

A slider for a slide fastener is provided with an openable bridge suitable to remove or replace a pull tab, wherein a base of the bridge is connected to the slider body by a connection allowing a combination of linear displacement and pivoting relative to the slider body, a linear displacement of the bridge causes the lock/unlock of the bridge to/from a retaining member of the slider body, and a pivoting of the bridge causes the opening/closing of a front passage for removal or insertion of a pull tab. The bridge portion may also include a locking member associated with the bridge.

TECHNICAL FIELD

The present invention refers to a slider for a slide fastener. More indetail, the invention relates to a slider with a bridge that can beshifted between a first position and a second position, for example toremove or replace a pull tab.

BACKGROUND OF RELATED ART

A slide fastener basically comprises a pair of tapes bearing respectiverows of teeth, top and bottom stops, and a slider with a pull tab. Theslider basically comprises an upper blade, a lower blade, a centralportion between the upper and lower blade, which is called diamond, anda bridge extending over the upper blade. The pull tab is insertedbetween the bridge and the upper blade and is held in position by thebridge.

A technical problem encountered in the current technique ofmanufacturing slide fasteners is the need of a removable pull tab.

A removable pull tab may be desired for example to avoid damage of thepull tab caused by the manufacturing process of the slide fastener, orof the item (e.g. suit, bag, etc.) comprising the slide fastener. Forexample, it may be desirable to protect an expensive metal puller frommanufacturing steps such as sewing and finishing. Especially in thefield of luxury goods, the pull tab may be a delicate and expensiveitem. It should also be considered that a damage of the pull tab islikely to be visible and disappointing for the customer.

The above problem could be avoided by adding the pull tab at a finalstage of the manufacturing process. However, it is often desirable toopen and close the slide fastener during the process, which is mucheasier if the pull tab is mounted. In some embodiments of slidefasteners, the pull tab is indispensable to release a locking device andopen the slide fastener. Another reason to provide a removable pull tabis customization of the slide fastener.

A known solution is the use of a disposable plastic pull tab during themanufacturing process, which however has some disadvantages includingthe need of ab additional disposable pull tab and the step of cutting orbreaking the plastic pull tab at the end of the process, for insertionof the true pull tab intended for the product.

EP 2 322 050 discloses a process for making a slide fastener wherein aprotective cap is applied on the front portion of a resilient member ofthe slider. The protective cap allows easy insertion of a puller and,where appropriate, releases a locking device of the slider, thusallowing the opening and closing of the slider without the puller. Thissystem is satisfactory but still has the drawback of requiring anadditional item, that is the protective cap.

Other prior art solutions of sliders with interchangeable pull tabinvolve a complicated design of the slider body, including for example aslidable pull tab carrier, see e.g. EP 1 987 730.

SUMMARY

The purpose of the invention is to avoid the above drawbacks of theprior art. The aims of the invention include the provision of a simpleand cost-effective slider with a removable and interchangeable pull tab,as well as a releasable locking system.

The aims are reached with a slider for a slide fastener according to theindependent claim 1. Preferred features are stated in the dependentclaims.

The slider body includes a diamond, an upper blade, a lower blade and abridge. Said bridge is connected to the slider body by connection meansallowing a combination of linear displacement and pivoting relative tothe slider body between two end positions. Said two positions include:i) a first position wherein the bridge is engaged with a retainingmember of the slider body, and ii) a second position wherein the bridgeis disengaged from said retaining member and is rotated relative to theslider body.

The first position can be termed “closed” and the second position can betermed “open”. The bridge in the second position may define a frontpassage suitable for insertion or removal of a pull tab. Said passage isclosed when the slider is in the first position, thus holding the pulltab in place.

Said linear displacement is preferably in a longitudinal direction ofthe slider. Said term of longitudinal direction denotes a directionwhich is parallel to the sliding direction of the slider. In someembodiments, it is substantially parallel to the upper and lower blades.

Preferably, the bridge is connected to the slider body via a rotationpin inserted in at least one slot. Hence, the rotation pin provides thepivoting feature while the slot provides the linear displacementfeature. In a preferred embodiment a rotation pin is fixed to the sliderbody and the bridge comprises one or more slot to engage said pin. Apreferred embodiment has a fixed pin and sliding slot(s); alternativeembodiments may be realized with a sliding pin.

Preferably, the slider comprises elastic means disposed to urge thebridge in the first position. More preferably, said elastic means areconfigured to oppose the linear displacement of the bridge relative tothe slider body. In a preferred embodiment, said elastic means arehoused in the bridge. The elastic means may be for example a coilspring. Preferably the elastic means are energized (for example a springis slightly compressed) when the bridge is in the first position.

In some embodiments of the invention, the slider comprises also lockingmember to prevent undesired sliding.

The locking member, for example, may be configured to protrude throughan opening of the upper blade, in such a way that when the slider isfitted on a slide fastener, the locking member is able to engage theteeth in the region between the upper and lower blades, thus locking theslider itself.

One of the preferred aspects of the invention is the integration betweenthe bridge and the locking member. Preferably, the locking member isengaged when the bridge is in the first position, and is released whenthe bridge is in the second position.

In a particularly preferred embodiment, said locking member isassociated to the bridge, for example it is at least partially insertedin a recess of the bridge. Both the locking member and the bridge arepivotable together around a pin; the locking member however has only thedegree of freedom of pivoting around said pin, while the bridge is alsolongitudinally slidable relative to said pin. More preferably, saidelastic means act between the bridge and the locking member.

In a preferred embodiment, the locking member comprises a cam whichcopies a profile of the bridge, suitable to provide at least a partialdisengagement of the locking member upon displacement of the bridge.

A pull-tab can be easily removed or replaced by opening and closing thebridge. Hence, for example, a temporary pull-tab can be insertedwhenever necessary during the manufacturing process of the slidefastener, or of an item comprising the same. Then the temporary pull tabcan be removed and a final pull tab inserted. Opening the bridge portionof the slider is easy but, at the same time, the closure is safe andreliable thanks to the combined pivoting and displacement.

Another advantage is the simple construction of the slider body. Theinvention eliminates the need of expensive design of the slider body,including moving parts such as slidable pull tab carrier and/or elasticmembers mounted directly in the slider body.

The bridge in the open position can be used as a puller, which meansthat the slide fastener can be operated (e.g. during the manufacturingof an item) even without a pull tab.

Another advantage of the invention is the full integration with alocking system when provided. Since the locking member is associatedwith the bridge, the locking of the slider is automatically released byopening the bridge, even without a pull tab.

These and further advantages of the invention will be more evident fromthe detailed description provided here below, given as indicative andnot limiting example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a slider according to an embodiment of theinvention, in a first closed/locked position.

FIG. 2 is a cross section of the slider of FIG. 1, according to a medianvertical plane.

FIG. 3 is a side view of the slider of FIG. 1 with the bridge in anintermediate unlocked position.

FIG. 4 is a cross section of the slider in the position of FIG. 3according to a median vertical plane.

FIG. 5 is another cross section of the slider of FIG. 3, according to avertical plane passing through one of the slots of the bridge.

FIG. 6 is a side view of the slider of FIG. 1 with the bridge in asecond and open position.

FIG. 7 is a cross section of the slider of FIG. 6 according to a medianvertical plane.

FIG. 8 is an exploded view of the slider of FIGS. 1 to 7.

FIG. 9 shows the insertion or removal of a pull tab to/from a slideraccording to the invention.

FIGS. 10 and 11 are sectional views of a slider according to anotherembodiment.

DETAILED DESCRIPTION

The figures show a slider 1 for a slide fastener, which basicallyincludes a slider body 10 with a diamond 11, an upper blade 12, a lowerblade 13 and a bridge 14.

The bridge 14 is shiftable between a first position of FIG. 1, and asecond position of FIG. 6.

The second position of FIG. 6 is also termed open position, since therotated bridge 14 defines a front passage 33, which is suitable forinsertion or removal of a pull tab 40 (see also FIG. 9).

The first position of FIG. 1 is also termed closed position, since thefront passage 33 is closed and a pull tab can be held in place betweenthe bridge 14 and the upper blade 12.

In the first position, the bridge 14 is engaged with a retaining member19 of the slider body 10 (FIG. 2). A spring 24 housed in a seat 30 ofthe bridge 14 serves to normally keep the bridge 14 in the firstclosed/locked position.

The bridge 14 can pass from the first position of FIG. 1 to the secondposition of FIG. 6 by a linear displacement followed by a rotationaround a pin 17. The linear displacement (FIGS. 3 to 5) disengages thebridge 14 from the retaining member 19; the rotation around the pin 17(FIGS. 6, 7) opens the front passage 33.

Referring more in detail to the embodiments of the figures, the bridge14 comprises a base 15 and a distal end 16 opposite to said base 15. Therotation pin 17 is fixed to the slider body 10 and is received in a pairof slots 18 of said base 15.

The slots 18 are formed on lower projections 31 of the base 15. Saidslots are denoted by the slotted line of FIG. 1; one of the slots isvisible in the cross section of FIG. 5 and the two slots are alsovisible in the exploded view of FIG. 8. The connection via pin 17 andslots 18 gives the bridge 14 the ability to linearly slide from theposition of FIG. 1 to the position of FIG. 3, and to rotate to reach theopen position of FIG. 6.

The distal end 16 is suitably configured to engage and disengage theretaining member 19 upon a linear shift of the bridge 14. For examplethe front of the distal end 16 has a suitable recess 20 for engagementwith a projecting tooth 21 of said retaining member 19. The retainingmember 19 is integral with the slider body 10 (FIG. 2).

The embodiments of the figures also comprise a locking member 22.According to a preferred embodiment, said locking member is fitted inthe bridge 14.

Said locking member 22 has a protrusion 23 adapted to engage the teethof a sliding fastener (not shown) operated by the slider 1, to preventundesired opening of the slide fastener.

In the first position of FIGS. 1 and 2, the protrusion 23 of the lockingmember 22 inserts into a passage 32 of the upper blade 12, thus reachingthe teeth in the region between the two blades 12, 13. By abuttingagainst the teeth, said protrusion 23 locks the slide fastener. Hencethe position of FIG. 1 is also a locked position of the slider 1. On theother hand, the second position of FIGS. 6 and 7 has the locking member22 raised together with the bridge 14, which means that the lock isreleased and the slider 1 is free.

It should be appreciated that the locking member 22 can pivot togetherwith the bridge 14 around the same pin 17. However, the locking member22 can only rotate around the pin 17, while the bridge portion 14 hasalso the additional degree of freedom of a certain linear translation,thanks to the slots 18.

The assembly of bridge 14 and locking member 22, in accordance with theshown embodiment, can be fully appreciated looking at FIG. 8.

The pin 17 is inserted through and supported by projections 25 of theupper blade 12 of slider body 10. The locking member 22 is partiallyreceived in a seat 26 of the bridge portion 14, in such a way that ahole 27 of said locking member is aligned to holes 18 of saidprojections 25 and faces the slots 18. Hence, the pin 17 is insertedthrough the holes 28 of said projections 25, the hole 27 of the lockingmember 22, and the slots 18 of the bridge 14.

The hole 27 of the locking member 22 has substantially the same diameterof the pin 17, while the slots 18 are larger than said pin 17 in adirection of sliding of the bridge 14, which is the longitudinaldirection in the figures as denoted by d in FIG. 3.

The coil spring 24 abuts against the bottom of the seat 30 and against asurface 29 of the locking member 22.

As already mentioned above, the locking member 22 has only one degree offreedom and can only pivot around the pin 17, while the bridge 14 isalso allowed to longitudinally slide by the displacement of the pin 17in the slots 18.

Due to the elastic force of spring 24, the bridge 14 and the lockingmember 22 can rotate together around the pin 17, during the opening ofthe bridge 14, as if they were a rigid body. However, the bridge 14 canalso slide in a linear fashion, relative to the locking member 22 andslider body 10, compressing or releasing the spring 24.

The locking member 22 comprises also a cam 34, on the opposite part ofthe locking protrusion 23 relative to the pin hole 27. Said cam 34engages a respective profile 35 made in the base 15 of the bridge 14.

Another embodiment is illustrated by FIG. 10 (released) and FIG. 11(locked). In this embodiment, a different accommodation of the coilspring 24 is provided. Instead of the seat 30, the locking member 22 hasa step 37 forming a plane surface substantially parallel to the oppositesurface of the bridge 14. Hence, the coil spring 24 can be receivedbetween the locking member 22 and bridge 14 without the need of making adeep hole in the bridge 14. This embodiment may be preferred to ensureeven better and smooth operation of the coil spring. Another advantageof this embodiment is that the bridge 14, in particular the base 15, issimpler to manufacture.

The slider 1 operates in the following manner.

In the closed/locked position of FIGS. 1-2, the coil spring 24 isslightly compressed. Due to its position and inclination, the spring 24keeps the bridge 14 in the closed position, by urging the distal end 16against the retaining member 19 (FIG. 2). At the same time, the spring24 tends to rotate clockwise the locking member 22 around the pin 17, sothat the locking member 22 is also urged in its locked position, againsta step 36 of the slider body 10, as shown in FIG. 2. The protrusion 23is fully extended in the passage 32, for engagement with the teeth ofthe fastener.

The locking member 22 can be released by a pull tab during the normaluse, lifting the middle of the locking member around the pin 17 untilthe teeth are freed from the protrusion 23. The bridge 14 in this casewill remain in its closed position, due to the engagement of frontrecess 20 and retainer 19, which is unaffected by the action on the pulltab.

FIG. 3 shows how to open the bridge 14. The bridge 14 is first pushed asdenoted by d, relative to the slider body 10 and locking member 22,against the spring 24 which is further compressed. By doing so, thedistal end 16 is progressively disengaged from the retaining member 19as seen in the sectional view of FIG. 4.

The pin 17 slides from one end to another end of the slots 18, that isfrom left end to the right end in the figures. In the meantime, thelocking member 22 is rotated around the pin 17 by the cam 34 copying theprofile 35, thus starting to disengage the lock.

When fully released from the retaining member 19, the assembly of bridge14 and locking member 22 (hold together by the action of the spring 24)is free to pivot around the pin 17, reaching the open position of FIGS.6 and 7.

The rotation of the bridge 14 opens the front passage 33 which allowsinsertion or removal of a pull tab. The locking member 22 is released aswell, pivoting together with the bridge 14 and bringing the protrusion23 away from the locking position in the passage 32.

The skilled person will realize that inserting or replacing the pull tabis quite easy, as shown by FIG. 9. Further to this, the same bridge 14,when in the open position of FIG. 6, could be used to manually open orclose the slide fastener. In other words, when the bridge 14 is openedand the locking member 22 is also released, the bridge itself can beused as a sort of puller. This feature may be useful during amanufacturing process of the slide fastener or of an item comprising thesame, because the slide fastener can be opened or closed even without apull tab.

The closing of the bridge is as follows. Starting from the open positionof FIG. 6, the bridge 14 is lowered until it is substantiallyhorizontal, then it is shifted back to the position of FIG. 1, slightlycompressing the spring 24. When the position of FIG. 1 is reached, thesystem is stable thanks to the spring 24 urging the end 16 against theretainer 19 and the locking member 22 against the step 36 of the body10.

The figures show also the advantage of a simple construction, especiallyof the slider body. The slider body 10 has no moving parts and thespring 24 is fully received in the slider bridge 14. No hole or seat fora spring is to be provided in the body 10. Another advantage is that asingle elastic element, such as the spring 24, keeps both the bridge 14and the locking member 22 in the closed/locked position. The inventioncombines the functionality of an openable bridge, removable pull tab andreleasable locking system, in an efficient and cost-effective manner.

1. A slider for a slide fastener, comprising: a slider body including adiamond, an upper blade, a lower blade and a bridge, wherein the bridgeis connected to the slider body by a connection allowing a combinationof linear displacement and pivoting of the bridge relative to the sliderbody, and wherein the linear displacement and pivoting of the bridgetakes place between: i) a first position wherein the bridge is engagedwith a retaining member of the slider body, and ii) a second positionwherein the bridge is disengaged from the retaining member and isrotated relative to the slider body.
 2. The slider according to claim 1,wherein the linear displacement of the bridge relative to the sliderbody causes the engagement or disengagement of the bridge to/from theretaining member.
 3. The slider according to claim 1, wherein therotation of the bridge relative to the slider body causes opening orclosing of a front passage between the bridge and the slider body, thefront passage being suitable for insertion or removal of a pull tab. 4.The slider according to claim 1, wherein the bridge has a baseassociated to the slider body by the connection, and a distal endopposite to the base, the distal end being engaged with the retainingmember when the bridge is in the first position, and disengagedtherefrom when the bridge is in the second position.
 5. The slideraccording to claim 3, wherein a linear displacement of the bridgerelative to the slider body causes a lock/unlock of the distal endto/from the retaining member, and a pivoting of the bridge portioncauses the opening/closing of the front passage.
 6. The slider accordingto claim 1, wherein the connection includes a rotation pin inserted inat least one slot.
 7. The slider according to claim 6, wherein therotation pin is fixed to the slider body, and wherein the at least oneslot is formed in a portion of the bridge.
 8. The slider according toclaim 1, wherein the linear displacement is in a substantiallylongitudinal direction of the slider.
 9. The slider according to claim1, further comprising an elastic member configured to urge the bridge inthe first position.
 10. The slider according to claim 9, wherein theelastic member is housed in the bridge.
 11. The slider according toclaim 1, further comprising a locking member to prevent sliding, thelocking member being in a locked condition when the bridge is in thefirst position, and being in a released condition when the bridge is inthe second position.
 12. The slider according to claim 11, wherein thelocking member is associated with the bridge, both the locking memberand the bridge being pivotable together around a same pin fixed to theslider body.
 13. The slider according to claim 12, wherein the lockingmember comprises one degree of freedom of pivoting around the pin, whilethe bridge is slidable relative to the pin.
 14. The slider according toclaim 11, further comprising an elastic member configured to urge thebridge in the first position, wherein the elastic member acts between asurface of the bridge and a surface of the locking member, and whereinthe bridge and the locking member are urged one against the other by theelastic member, so that they form a substantially rigid assembly whenrotating around the pin.
 15. A slide fastener, comprising a slideraccording to claim 1.